Grade meter



F. w. THOMPSON GRADE METER Filed April 15 1921 2 Sheets-Sheet l lVl/EN TOR l L THOMRSON) q'fwm i ATTORNEYS Aug. 5, 1924'.

F. W. THOMPSON GRADE METER Filed April 15 1921 2' Sheets-Sheet 2 Patented Aug. 5, 1924.

STATES.

1563,72 PATENT; OFFIQEL;

FR-ED WMQ THoivIiPsoN; or PALMS-,C'ALIFOBNIA, ASSIGNOR- or ONEJ-IALF T0 BURT C. HUNNICUT'I, OF LOS ANGELES, CALIFORNIA.

GRADE METER.

' 1 Application filed Apr1115,1921. Seria1No.41,56*1.

T o a ll whomitmay oeaeemc r i i Be t; lm njt h yl, F E NV IAM Trrorrrsom a citizlen of the United States, and a resident of, Palmalin the county of L05 Anee esiandSwept i r ve invented certain neWj and useful Improve- 911 ow ns a' p ficatioa: a a l a The present invention relates in general to grade meters, and more particularly to grade meters for use With vehicles. I v

@11 ob e 1" the in e io i i v Pr i aa grade meter fonuse with land, water or air vehicles, such asautomobiles, ships, aeroplanesorthe; like, which will afford an ac-, urat i di et n f he r d wh -h r it be ascending or descending, which will not be afiectedby changesinthedirection or rate, of motion of the vehicle and which is of Simple, durable and gcompact construction, reliable in operation,; easy and inexpensive to vmanufacture and apply and attractive in appearance. i i i i 5 Other ,b'ectsandadvantagesof the invention reside incert-ain novelfeatures of construction, combination and arrangement of parts which Will hereinafter more fully described and particularly pointed out vin the appended claims, referencebeing had to the accompanying drawings forming partfof thiss'pecification, and idavhich: I Eigurelis a front elevational viewof-the grade metered 1 e Figure: vertical sec;

tional "vieiv (thereof; parts being shown in elevation for the sake of i1lustration wF su 3. a t ansver v cal Se a view thereof, oniline3+3 of. Figure 2, partsbsin sheen i e a o fe k o illustration; h l i 'Figure his a detail view partly in sec tio ndicate and itsf associated. structure tall perspective view of trat ng the arrangement for stabilizing hflgqil, '4

p "ings wherein for the? sake of llustration is sho vn the preferred embediment of the invention, the numeral 19 designates generallya casing adapted to he associated with an instrument board, deseared at l l vlrich;constitutes a stationary new li r l injGrade Meters; of: which the fol-1 u d par y; in} levat 0. f t b g,

perspective iIlus The grade meter includes an indicator having a circular casinglll, integral or suitablysecured tothe casinglO, andhaving a window; 12 therein; A A circular; panel 1301f glass. or other transparent material extends across the window 12. A pair of {spaced plates designated at 14 is arranged within the casing of the indicator and these plates are maintained in spaced. relation by means, of rivets or the like indicated at 15.; The exposed face of theouter of these plates has arranged thereon a-chart 16 which lies adjacent to the Window 12 and immediately behind the glass panel 13. The chart carries an outer and inner circumferentialseriesof indicia, designated atlZ andlS, respectively Which serve to indicate the degree of the grade. Preferably the outer series, .desig} nates the degree of the grade if it be an up grade and an inner series designates the degree ofthe grade it itbe a down-grade Radial lines f19 divide the chart into a phi: rality f angular spaces and facilitate the readingof the indicia. A pointer 20 coacts Withthe chart to afford the indication of the gradefi The pointer 20 is fixed by ineansfof a nut2l to the outer end of a rotatable shaft 22' (see'Figure a) Theshaft 22 is rotatably journaled in a bushing 23, Whi ch 7 extends be tween and is carried the spaced plates 14 and which is provided with reduced exten sions 24: extending through suitableopenings provided therefor in the plates andretained 1n position by means of nuts 25'threaded on the reduced extensions and bearing against the plates. A nut 26 is threaded on the shaft 22 at the end thereof which carries the pointer and prevents longitudinal dis placement or the shaft one directionielA Washer 27 isarranged on the shaft 22m ns opposite endfromthe pointer and is interposed between the bushing28 and agents formed or, f xed on the end of the shaft 22 and hereinafter fully described, and in this manner displacementiof the shaft the other directionis prevented. l l Gravity controlled means is provided for governing or actuating the indicato and includes an arbor 28 carried by the casing 10, and a pivoted control plate29 h2n'ing a hub 29? rotatably mounted upon the arbor 28, The pivoted control plate is proiided with cutaway portions3 0 and With counter-j Weights S1 to effect' the proper balancing thereof. The provision of the counterweights and the cutaway portions makes possible to use a control plate of the required mass and balance without the necessity of having alarge and bulky structure. Stop lugs 32 are provided at the upper ends of the control plate and cooperate with the casing 10 to limit the movement of the control plate in either direction.

Motion transmission means is provided between the control plate and the rotatable shaft ofthe indicator and perferably consists of a segmental gear 33 fixed to the marginal edge of the control plate and a pinion 34: fixed to the adjacent end of the rotatable shaft of the indicator and meshed with the segmental gear 23 of the control plate.

Means is provided for retarding or clampening the action of the gravity controlled means and preferably comprises a reservoir or tank 34 carried by the lower end of the casing 10. The reservoir is filled or partly filled with oil or other fluid of suitable viscosity, designated at 36, and a portion of the control plate is immersed in the oil or fluid of the reservoir and operates therein. This oil or fluid presents a resistance to the motion of the'control plate which affords the proper retarding or dampening actionto prevent changes in the speed, or direction of motion of the vehicle from affecting the control plate. Preferably the control plate is provided with a lateral fin or projection 37 to increase the resistance offered to the motion of the control plate by the fluid. A plurality of spaced and staggered baffle plates 38 depend from a solid carrier or master plate 39 and coact with staggered upstanding baffle plates 40 carried by the bottom of the reservoir to stabilize the fluid itself within the reservoir. The master plate being solid and the baffles being spaced and staggered they do not interfere in any way with the motion of the control plate. The baflie plates arranged along one side of the control plate are provided with a series of openings or recesses 37 to accommodate the lateral fin 37 in its motion. A plugged opening 41 is provided in the reservoir to facilitate the charging and replacing of the fluid;

In operation after the grade meter has been placed on the vehicle it will serve to indicate with precision the degree of the grade, whether the grade be an upgrade or a down-grade. The'control plate which is suspended so as to be controlled by gravity maintains the same relation with respect to the center of the earth and as the vehicle or a other elementsof the grade meter change An important feature of the present invention resides in the means provided for retarding or dampening the action of the gravity control means. These means being necessarily of considerable mass, changes in the direction or degree of the motion of the vehicle upon which it is suspended tend to influence it so that it would incorrectly move the pointer and present a false or incorrect indication. In the present invention, however, this is prevented as' the oil or other fluid operates upon the control plate and prevents motion of the control plate in response to the forces incident to changes in the direction or rate of motion which play upon the control plate, and permit the control plate to respond only to the action of gravity and to allow the casing to partake of the-relative motion requisiteto proper indication of the grade.

I claim 1. In a grade meter, a casing, an indicator including a chart, a pointer coacting with the chart and a, rotatable shaft carrying the pointer, gravity control means for governing the indicator including a pivoted control plate, motion transmission means between the plate and the shaft including a segmental gear fixed to the plate and a pinion fixed to the shaft and meshed with the segmental gear, means for retarding or dampening the action of said gravity control plate comprismg a reservoir, having fluid therem in which a portion of said control plateis immersed and operates, and stop lugs carried by the control plate and engageable with the casing for limiting the motion of the control plate in either direction. 7

2. In a grade meter, a casing, an indicator, gravity controlled means for governing said indicator including a pivoted control plate having a lateral fin and means for retarding or dampening the action of said gravity control plate comprising a reservoir having oil or the like therein in which a portion of said control plate and the fin is immersed, and baffies for retarding movement of the oil in said reservoir said baffles having recesses tgherein to accommodate the motion ofsa'id IL 3. In a grade meter, a casing, an indicator, gravity controlled means for governing said indicator including a pivoted control plate and means for retarding or dampening the action of said gravity control plate comprising a reservoir having oil or the like therein in which a portion of said control plate is immersed, and baffles for retarding movement of the oilin saidireservoir.

4.111 a grade meter, an indicator including a pair of spaced plates, a chart arranged upon theexposed face of the outermost of said'plates, a bearing bushing carried by said plates, nuts securing said bushing in posi tion, a rotatable shaft journaled in said bearing bushing, a pointer carried by one end of said shaft and coacting With said chart, and gravity controlled means cooperable With the other end of said shaft for governing said pointer.

5. In a grade meter, an indicator including a chart, a pointer coacting With said chart and a rotatable shaft carrying said pointer, gravity controlled means for governing said indicator including a pivoted control plate having cutaway portions and counterweights to effect the balancing thereof and motion transmission means between said control plate and said shaft.

FRED WM. THOMPSON, 

